Fibrinogen-based tissue adhesive containing an elastase inhibitor

ABSTRACT

The present invention provides a fibrinogen-based tissue adhesive which contains an elastase inhibitor.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation application claiming priority to U.S.application Ser. No. 09/486,516, filed Jun. 7, 2000, which is a U.S.National Phase Application, filed under 35 U.S.C. §371 of PatentCooperation Treaty Application Number PCT/AT98/00202, filed Aug. 26,1998, which is claims priority to Austrian Patent Application AT1449/97, filed Aug. 28, 1997. Each of the aforementioned applicationsare hereby incorporated by reference in their entirety and for allpurposes.

STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSOREDRESEARCH OR DEVELOPMENT

Not Applicable

REFERENCE TO A “SEQUENCE LISTING,” A TABLE, OR A COMPUTER PROGRAMLISTING APPENDIX SUBMITTED ON A COMPACT DISK.

Not Applicable

BACKGROUND OF THE INVENTION

The invention relates to a fibrinogen-based tissue adhesive.

Fibrinogen-based tissue adhesives which can also be called fibrinadhesives, in their adhesive action imitate the final phase of bloodcoagulation. In this instance, fibrinogen is cleaved into fibrinmonomers by the action of thrombin which mostly is added to thefibrinogen solution during the glueing procedure, which, however, isalso present in every wound. The fibrin monomers agglomeratespontaneously to arranged fiber-type structures called fibrin. Thisfibrin monomer aggregate then is further stabilized under the action offactor XIIIa by covalent cross linking. At this, in a transamidizingreaction, peptide bonds form between specific glutamine and lysine sidechains of the fibrin monomers. The factor XIIIa which likewise iscleaved by thrombin from inactive factor XIII is an active transamidaseand, on account of its action, it is also called “fibrin-stabilizingfactor”.

Although, when applying a tissue adhesive, in principle the sameprocesses occur as in “natural” blood coagulation, in a tissue adhesivethe participating components and factors are more concentrated by amultiple than in blood. Due to this, the coagulation of blood alsooccurs much more rapidly, and the achieved tissue sealing or the formedblood clot are much safer and also more stable.

A prerequisite for the breakthrough of the fibrin adhesives at the endof the 70's was the progress in the fractionation and purification ofblood coagulation factors. Because of this it was possible to preparethe natural coagulation factors with such purity and at such aconcentration as is required for an efficient tissue adhesion. The firstcommercially available tissue adhesives were launched on the market atthe end of the 70's, and since then they have proven suitable in a largenumber of possible fields of application; primarily in those fields inwhich the use of conventional surgical techniques repeatedly haveresulted in severe problems, e.g. with severe hemorrhages, when glueingnerves or when inner organs, such as the liver and spleen, were torn.

A further advantage of a fibrin adhesive in contrast to sutures usingneedle and thread resides in that the tissue or organ to be treated isnot additionally damaged by the sewing procedure, and therefore, whenusing tissue adhesives based on fibrinogen, there are much fewercomplications and less obtrusive scars than with conventional surgicalsutures. Besides the optimum adhesive effect which comprises a high loadbearing capacity and a high inner strength of the sealing as well as agood adherence of the adhesive to the wound or tissue surfaces,respectively, also the processes immediately following adhesion areessential for optimizing tissue adhesives (cf. AT-B-359 652 and 359653). Among them are the control of the durability of the sealant withinthe body as well as their capability of being absorbed and theadhesive's properties of enhancing wound healing.

Therefore, for a tissue adhesive not only the rapid and secure sealingeffect is of decisive importance but also that the sealant formed or theblood clot formed, respectively, dissolve again in the body within acertain period of time and the wound completely heals up as aconsequence of the complete absorption of the formed clot.

In this connection, it is necessary to also control, the (endogenous)process of dissolving the formed blood clot, i.e. the fibrinolysis, byoptimizing the tissue adhesive.

In fibrinolysis, the fibrin present in the blood clot formed is degradedand/or removed, and thereby the blood clot is dissolved. At first, underthe influence of intrinsic or extrinsic plasminogen activators, such asblood coagulation factors XI and XII, prekallikrein, urokinase or t-PA,the fibrinolytically active plasmin is formed from the inactiveplasminogen, said plasmin also cleaving fibrinogen and the bloodcoagulation factors V and VIII in addition to fibrin.

Since the endogenous fibrinolysis processes mostly start immediatelyafter formation of a clot and thus there is a risk that an existingtissue sealant will not adhere good enough or that a clot formed willbecome destabilized too early, it has become a rule in tissue glueing toprovide for the addition of a plasmin inhibitor or a plasminogenactivator inhibitor so as to inhibit the action of plasmin directly orindirectly, to thus protect the sealant, primarily in its initial phase,from a premature fibrinolysis. With the concentration of the inhibitoralso a targeted control of the dissolution times (lysis times) of theclot formed or of the sealant, respectively, is possible. The larger theamount of inhibitor provided, the more stable the clot relative tofibrinolysis, i.e., the longer will this clot remain stable and thelonger will it take for the adhesive to be completely absorbed.

Thus, when using the fibrinolysis inhibitor, an optimum balance must befound between preventing premature fibrinolysis and an as rapid aspossible wound healing process.

In the commercially available tissue adhesives, aprotinin is used as theplasmin inhibitor, which is also called bovine basic pancreatic trypsininhibitor. Aprotinin is a polyvalent proteinase (kallikrein) inhibitorand inhibits coagulation factors XIIa, XIa, VIIIa as well as, primarily,plasmin and plasmin activators, but also trypsin, chymotrypsin andkallikrein.

Previously, aprotinin has mainly been produced from cattle. Due to theproblems involved in the use of bovine material in medicaments which areused for the treatment of humans, however, more and more frequentlyrecombinantly prepared aprotinin is being used.

In tissue sealants, aprotinin is used in an amount of from 20 to 3000kallikrein inactivator units (KIU)/ml tissue adhesive as a rule, itsoptimum concentration depending on the fibrinolytic activity of therespective tissue. However, it has been shown that mainly in tissueswith high fibrinolytic activity, the fibrinolysis-inhibitory action ofaprotinin can be controlled to a very limited extent only, despite theuse of high aprotinin concentrations, and thus undesired, early lyticprocesses may occur.

SUMMARY OF THE INVENTION

Thus, it is an object of the present invention to provide a tissueadhesive with which the disadvantages of the prior art are overcome andwith which also primarily with tissue sealants in wounds exhibiting ahigh plasmin activity, a satisfactory and reliable protection against apremature fibrinolysis will be ensured, wherein the quality of theadhesion must not be negatively affected.

According to the invention, this object is achieved by afibrinogen-based tissue adhesive which is characterized in that itcomprises an admixed elastase inhibitor. For, surprisingly, it has beenshown that the fibrinolysis process cannot only be prevented byinhibiting plasmin or by inhibiting the activation of plasminogen toplasmin, but also by elastase inhibitors or by inhibitors whosefibrinolysis-inhibiting action is mainly based on a non-plasminfibrinolysis mechanism, respectively. For reasons of simplicity, suchnon-plasminogen fibrinolysis inhibitors are encompassed by the term“elastase inhibitor” for the purposes of the present invention. It hasbeen speculated that besides the plasmin-mediated fibrinolysis, alsofurther fibrinolytic processes might exist which are not based onplasmin (e.g. a lysosomal process; cf. Simon at al., BLOOD 82 (8)(1993), pp. 2414-2422), and which cannot be substantially inhibited byaprotinin; yet, it has also been shown that this non-plasminfibrinolytic pathway could not be inhibited by specificelastase-inhibiting peptides, such asN-methoxy-succinyl-L-alanyl-L-prolyl-L-valanyl chloromethyl ketone(AAPVCK), either (cf. Simon et al.). It was the more surprising that itcould be found out in the course of the present invention thatinhibitors which do not have any (substantial) plasminor plasminogenactivator-inhibiting activities, i.e. the elastase inhibitors of theinvention, can ensure a very well controllable lytic process of the clotformed both in vitro and in vivo. This proved particularly suitable intissues with increased fibrinolytic activity in which they can preventearly lysis even at moderate concentrations.

Premature lysis also plays a role in tissues with high fibrinolyticactivity, primarily within the first time after the sealing has beenmade, since premature lysis may lead to a (partial) detachment of thesealant and, thus, to rebleeding.

Furthermore, it has been shown that the elastase inhibitor to be usedaccording to the invention in the tissue adhesive exhibited itsfibrinolytic activity not only in combination with conventionalinhibitors acting on plasmin, but that even the entire fibrinolysisinhibition can be ensured by the elastase inhibitor alone. Oneparticular embodiment of the present invention thus consists in that thetissue adhesive does not contain any further active components besidesfibrinogen, the elastase inhibitor, and, optionally, factor XIII.

In the present adhesive, the fibrinogen concentration corresponds tothat of known tissue adhesives and, as a rule, should be at least morethan 50 mg, in particular more than 70-80 mg of fibrinogen/ml, i.e. atleast approximately the 20-fold of the fibrinogen concentration in blood(2-4 mg/ml). Preferably, the fibrinogen is present in a further purifiedform as compared to the cryoprecipitate.

Preferred elastase inhibitors within the scope of the present inventionare selected from the group of eglin, elastase-α₁-proteinase inhibitor,α₁-antiprotease, elafin, leukocyte protease inhibitor, in particular aleukocyte fraction, preferably a granulocyte-derived fraction, or humansecretory leukoprotease inhibitor, or mixtures thereof. As the leukocytefraction, e.g., a cell lysate, in particular one derived from humancells, may be used. Other elastase- or other fibrinolysis inhibitorswhich do not act on plasmin may be assayed by the skilled artisan fortheir usefulness in the tissue adhesive of the invention in a simplemanner by means of the assaying systems disclosed in the Examples or byapplying the elastase inhibiting assays known from the prior art. Thepreferred elastase inhibitors include also various derivatives of theelastase inhibitors of the invention, e.g. fragments or forms of theseinhibitors which have been modified chemically or by (recombinant)protein design, wherein, however, it is, of course, always necessarythat these derivatives have the qualitative elastase-inhibitor propertyof the basic inhibitor.

Preferably, the tissue adhesive according to the invention isexclusively comprised of human proteins, wherein also recombinantlyprepared human proteins are to be understood as being “human proteins”.Preferably, therefore, the proteins used in the tissue adhesive areprepared either from blood, plasma, cryoprecipitate, or from arecombinant cell culture.

A particularly preferred tissue adhesive is characterized in that it isexclusively composed from human blood or plasma proteins.

The ratio of the amounts of elastase inhibitor to mg of fibrinogenpreferably is from 1:100 to 1:150,000, preferably from 1:500 to1:110,000. Expressed in units of inhibitor to g of fibrinogen,preferably at least 10⁻⁶ U/g fibrinogen are admixed to the tissueadhesive. Particularly preferred is a range of between 10⁻³ and 10 U/gof fibrinogen. The amount of inhibitor admixed in the tissue adhesive ofthe invention, which inhibitor may also naturally be present in blood orplasma, respectively, preferably is at least 20×, in particular at least50× higher than its physiological concentration in blood or plasma,respectively. The tissue adhesive of the invention may, e.g., becomposed as follows: 75-115 mg/ml clottable protein, 50-110 mg/ml,preferably 70-110 mg/ml, thereof being fibrinogen; optionally 1-50,preferably 10-50, IU factor XIII/ml. As the inhibitor, e.g. eglin may beadmixed in an amount of between 1-100 μg/ml or α₁-antiprotease at 0.01-1U/ml. As a rule it will be sufficient to admix the elastase inhibitor inan amount which corresponds to the fibrinolysis-inhibiting activity ofaprotinin in known tissue adhesives.

Depending on the purpose of the sealing, the adhesive according to theinvention may contain plasminogen or may be free from plasminogen. Ifplasminogen is contained, it should be contained in an amount of atleast 0.0001 mg/mg of fibrinogen, preferably more than 0.001, inparticular more than 0.01. With the presence of plasminogen in thetissue adhesive, based on its activation to plasmin, it is also possibleto define the fibrinolysis properties of the tissue adhesive even moreclearly.

On the other hand, the tissue adhesive, in a further preferredembodiment, does not contain any plasminogen at all or contains only asmall amount thereof, respectively.

As has been mentioned, the presence of the elastase inhibitor as theonly fibrinolysis inhibitor in a tissue adhesive surprisingly sufficesfor the functionality of the adhesive according to the invention.Preferably, however, also a plasmin inhibitor or a plasmin activatorinhibitor is used besides the elastase inhibitor, which also contributesto a better control of lysis, of absorption, and thus of wound-healing.Preferred plasmin inhibitors or plasminogen activator inhibitors areprimarily aprotinin, but also α₂-macroglobulin, α₁-antitrypsin,ε-amino-caproic acid, tranexamic acid or mixtures of these substances.Although in some instances authors have also ascribed α₁-antitrypsin,e.g., certain actions on elastase, the substances mentioned here areviewed as plasmin or plasminogen activators, respectively, since this isthe primary activity exhibited by these substances in the present field.This, of course, also applies for the purposes of the present invention.Moreover, also anti-adhesive additives, e.g. hyaluronic acid, may becontained.

A further preferred embodiment of the tissue adhesive according to theinvention consists in providing an antibiotic in the adhesive, as hasalready been suggested in AT-B-369,990. Particularly preferredantibiotics are selected from the group of aminoglycosides, betalactams,polypeptides, phosphomycin, tetracyclines or mixtures thereof. In afurther preferred embodiment, the antibiotic is present in the form of apoorly soluble-derivative.

Preferably, also factor XIII is provided in the tissue adhesiveaccording to the invention so that the inner strength of the clot andthe strength and durability of the adhesion will be positivelyinfluenced. To this end, factor XIII is preferably used in an amount offrom 1-50 units/ml, preferably around 10 U/ml. Based on fibrinogen,factor XIII is preferably present in a minimum concentration of 0.001U/mg of fibrinogen, in particular at least 0.1 U/mg of fibrinogen.Depending on the type of adhesion or type of tissue, however, theoptimum factor XIII concentration may easily be optimized by any skilledartisan. If an antibiotic is present in the tissue adhesive, it isbasically recommendable to provide somewhat more factor XIII (cf.AT-B-369,990)

Preferably, the tissue adhesive according to the invention is free ofkininogenic proteins (such as, e.g., kallikrein, etc.), wherebyinterfering side reactions can be prevented from the beginning.

According to a preferred embodiment, the tissue adhesive according tothe invention is present in combination with a solid surface as afleece, whereby primarily for large-area wounds, an optimum woundclosure and an optimum covering will be attained. Examples of suchfleeces have been listed in AT-B 374,367. The solid surface of thefleece thus preferably is a collagen, gelatin or polysaccharide surface,wherein, of course, also further medically suitable surfaces whichoptionally may also have been impregnated for the specific purpose ofuse may be employed.

It has been shown that according to the invention, with the tissueadhesive comprising an elastase inhibitor a resistance to lysis can beachieved for a period of at least 10 hours, preferably 15 hours, even inan environment with high fibrinolytic activity. Resistance to lysisaccording to the present invention means that a respective fibrin clotwill not be degraded within a certain period of time, i.e. it remains inexistence. Determination of the resistance to lysis is, e.g., effectedby a photometric measurement in dependence on time. A preferred tissueadhesive according to the present invention thus has a resistance tolysis of at least 10 hours, preferably at least 15 hours, in anenvironment of high fibrinolytic activity. By “high fibrinolyticactivity”, e.g., a plasmin activity is understood which is above thephysiological plasmin potential. The fibrinolytic potential may, e.g.,be expressed by the plasminogen concentration (cf., e.g., Henriksson etal., Thrombosis Research 16: 301-312; 1979). This property of aresistance to lysis may be checked by any skilled artisan by a sampleassay, as described in the Examples.

When being applied, the tissue adhesive of the invention preferably ispresent in solution, yet for storage purposes, either deep freezing ofthe solution so that the tissue adhesive is present in deep-frozen form,or lyophilizing of the adhesive, i.e. providing it in lyophilized form,is recommendable. By “lyophilized form”, of course, only a tissueadhesive preparation made storable by freeze-drying is to be understoodwhich in a subsequent reconstitution thereof can be reconstituted almostcompletely ( i.e. to at least 80%) within a few minutes at 37° C.

The tissue adhesive according to the invention advantageously is presentin virus-inactivated force.

This inactivation treatment preferably is ensured by a tenside and/orheat treatment, e.g. by a heat treatment in the solid state, inparticular by a vapour treatment according to EP-0 159 311, or EP-0 519901 or EP-0 674 531.

Further treatments for inactivation of viruses also comprise a treatmentby chemical or chemical/physical methods, e.g. with chaotropicsubstances according to WO94/13329, DE 44 34 538 or EP 0 131 740(solvent), or photoinactivation.

Nanofiltration also is a preferred method for depleting viruses withinthe scope of the present invention.

According to a preferred embodiment, the elastase inhibitors admixedaccording to the invention may also be of recombinant origin.

Furthermore, the present invention relates to a tissue adhesive systemcomprising, as one component thereof, a tissue adhesive according to theinvention which comprises an elastase inhibitor.

As a rule, the tissue adhesive-system of the invention comprises athrombin component as a further component, in which thrombin is presenteither in liquid form or as a lyophilisate capable of beingreconstituted, wherein the thrombin component may have differentconcentrations when used in the adhesion, depending on the field ofapplication.

A tissue adhesive system which also falls within the scope of thepresent invention is characterized in that it comprises a fibrinogencomponent and a component separate therefrom which contains an elastaseinhibitor. As a rule, however, it is suitable to provide thefibrinolysis inhibitor component in the fibrinogen component (cf.AT-B-359;652 and 359,653). By suitable application devices, theinhibitor component may, however, also be supplied separately from thefibrinogen component. Preferably, that component which contains anelastase inhibitor at the same time also contains thrombin, it againbeing possible to provide this component either as a lyophilisate or asan (optionally deep-frozen) solution.

The tissue adhesive systems according to the invention further comprisesuitable application devices for the system component(s). In particular,double syringe systems as described in EV 0 037 393, EP 0 210 160 or EP0 292 472, or application devices as described in EP 0 315 322 or EP 0669 100 have proven suitable. With these special application devices,also those embodiments in which the inhibitor is applied in the thrombincomponent will yield reliable adhesive results.

The present adhesive is suitable for all the fields of knownapplications possible for fibrin adhesives. It has, however, provenparticularly suitable when providing adhesions in fields with highfibrinolytic activity. Thus, a subject matter of the present inventionis also the use of the tissue adhesive of the invention or of a tissueadhesive system of the invention, respectively, for producing apreparation or an application device, respectively, to be used in fieldswith high fibrinolytic activity, in particular in urology. A subjectmatter of the present invention is, moreover, a method for using atissue adhesive of the invention or a tissue adhesive system of theinvention, respectively, in surgery in fields involving highfibrinolytic activity, in particular in urology.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained in more detail by way of thefollowing Examples and drawing figures, to which, however, it shall notbe restricted.

FIG. 1 shows the decrease of-extinction corresponding to an increasinglysis of the clot

-   a) fibrin adhesive without aprotinin-   b) fibrin adhesive with aprotinin (1,000 U/ml)-   c) fibrin adhesive with alpha-1 PI (0.01 U/ml)-   d) fibrin adhesive with alpha-1 PI (0.001 U/ml)-   e) fibrin adhesive with alpha-1 PI (0.0001 U/ml);

FIG. 2 shows the decrease of extinction corresponding to an increasinglysis of the clot

-   a) fibrin adhesive with aprotinin (1,000 U/ml)-   b) fibrin adhesive with eglin (1 μg/ml)-   c) fibrin adhesive without aprotinin;

FIG. 3 shows the extent of rebleeding, expressed by the increase in theweight of the pre-weighed pads, in a hyper-fibrinolytic environment,which had been induced by infusion of t-PA; and

FIG. 4 shows the extent of rebleeding, expressed by the increase in theweight of pre-weighed pads, in an environment with normal fibrinolyticactivity, i.e. without t-PA infusion.

DETAILED DESCRIPTION OF THE INVENTION EXAMPLES

1. In Vitro-Tests for Assaying the Fibrinolysis-Inhibiting Action of theTissue Adhesive According to the Invention (at Present Considered byApplicant to be the Best Mode of Carrying out the Invention)

In this Example, blocking of the lysis of a tissue adhesive clot bymeans of eglin or α₁-antiprotease is shown. In this instance, the tissueadhesive STIM3 (IMMUNO AG, Vienna, AT) (comprising 70 mg offibrinogen/ml) is dissolved in water and subsequently diluted 1:6 withan 0.9 M NaCl solution.

This tissue adhesive solution is mixed 1:1 with a thrombin solution thathad been dissolved in 40 mM CaCl₂ and subsequently had been diluted witha 40 mM CaCl₂/0.9 M NaCl (1:5) solution to 0.1 U/ml, and pipetted on amicro plate, with 100 μl/well being provided.

Various concentrations of the inhibitors were added to each 5 μl oftissue adhesive (Eglin 1-100 μg/ml, α₁-antiprotease 0.01-1 U/ml).

For hardening of the adhesive, the microtiter plate was incubated at 37°C. for approximately 1.5 hours. The corresponding lysis reagents (a:cell-free supernatant from leukocyte homogenate (3× freezing/thawing) of500,000 leukocytes/μl; b: t-PA 2 mg/ml as positive control; NaCl 0.9% asnegative control) were then pipetted onto the clots (100 μl/well).Subsequently, the microtiter wells were measured in the plate photometerat 37° C. at a wave length of 405 nm kinetically over night 60×900 s inthe Photometer SLT 340 ATTC. The results are illustrated in FIGS. 1 and2, the decrease in the extinction corresponding to the increasing lysisof the clots.

It has been shown that both, with ≧1 μg of eglin/ml and with ≧0.01 U ofα₁-antiprotease/ml it is possible to prevent the lysis of the fibrinclot which occurs in the assay within 15 hours, which, on the one hand,is a hint to the central role played by the leukocyte proteases for thedegradation of the fibrin clot and, on the other hand, shows theexcellent effect of the inventive elastase inhibitors for preventingthis lysis.

2. In Vivo Activity of the Elastase Inhibitors Used According to theInvention

To determine the importance of leukocyte proteases, in particularelastase inhibitors, within the scope of the present invention, theeffect of the tissue adhesive of the invention both inhyper-fibrinolytic systems and in case of normal fibrinolytic activitywere tested to illustrate hemostasis by means of tissue adhesive andcompared with adhesives without inhibitors, and with an adhesivecontaining only aprotinin as plasmin inhibitor, respectively.

2.a) Hyperfibrinolysis

Anesthetized rabbits (2-3 kg) were heparinized (4,000 U/kg). Half anhour later, a part of the right liver lobe was clamped and partiallyresected distal from the clamp. Hemorrhages from larger vessels werestopped by electrocoagulation, and the residual diffuse haemorrhage wassealed by applying tissue adhesive (max. 4 ml) within 200 seconds. 10minutes later, infusion of t-PA (700 U/kg/h) was started, and the extentof rebleeding was determined for 2 hours by measuring the increase inweight of pre-weighed pads.

In doing so, 3 different tissue adhesives were tested.

a) Tissue adhesive (STIM3) with aprotinin (3,000 U/ml) as negativecontrol

b) Tissue adhesive (STIM3) without aprotinin as positive control

c) Tissue adhesive (STIM3) without aprotinin, with eglin (10 μg/ml);adhesive according to the invention

These adhesives were blind-tested and applied by means of a Duploject®syringe (from IMMUNO, Vienna, AT).

The results obtained are illustrated in FIG. 3.

2.b) Normal Fibrinolytic Activity

In addition to the hyperfibrinolysis-model, also the same assays werecarried out without t-PA infusion, yet with increased observationperiods of 4 hours. The results obtained are illustrated in FIG. 4.

It has been shown that both, in the hyperfibrinolysis model and withnormal fibrinolysis, reduced rebleeding is achieved as compared toconventional adhesives, with improved properties as compared toaprotinin, primarily in case of longer lysis periods.

These results prove the excellent effects of the tissue adhesivesaccording to the invention, with which an early lysis of the fibrinadhesive can be prevented, whereby rebleedings could be prevented alsoin fields with high fibrinolytic activity.

1. A fibrinogen-based tissue adhesive, characterized in that itcomprises an admixed elastase inhibitor.
 2. A tissue adhesive accordingto claim 1, characterized in that the elastase inhibitor is selectedfrom the group of eglin, elastase-α₁-proteinase inhibitor,α₁-antiprotease, leukocyte protease inhibitor, elafin, or mixturesthereof.
 3. A tissue adhesive according to claim 2, characterized inthat the leukocyte protease inhibitor is provided as a leukocytefraction, in particular a granulocyte-derived fraction.
 4. A tissueadhesive according to any one of claims 1 to 3, characterized in that itis composed exclusively of human proteins.
 5. A tissue adhesiveaccording to any one of claims 1 to 4, characterized in that it iscomposed exclusively of human blood- or plasma proteins.
 6. A tissueadhesive according to any one of claims 1 to 5, characterized in thatthe elastase inhibitor is contained in an amount ratio of from 1:100 to1:150,000, preferably 1:500 to 1:110,000, based on mg of fibrinogen. 7.A tissue adhesive according to any one of claims 1 to 6, characterizedin that at least 10⁻⁶ U of elastase inhibitor are contained per g offibrinogen, preferably between 10⁻³ and 10 U/g of fibrinogen.
 8. Atissue adhesive according to any one of claims 1 to 7, characterized inthat it contains plasminogen in an amount of at least 0.0001 mg/mg offibrinogen, preferably at least 0.001, most preferred more than 0.01. 9.A tissue adhesive according to any one of claims 1 to 7, characterizedin that it does not contain any plasminogen.
 10. A tissue adhesiveaccording to any one of claims 1 to 9, characterized in that it furthercomprises a plasmin inhibitor or a plasmin activator inhibitor whichpreferably is selected from the group of aprotinin, α₂-macroglobulin,α₁-antitrypsin, ε-aminocaproic acid, tranexamic acid, or mixturesthereof.
 11. A tissue adhesive according to any one of claims 1 to 10,characterized in that it comprises an antibiotic which preferably isselected from the group of aminoglycosides, betalactams, polypeptides,phosphomycin, tetracyclines or mixtures thereof.
 12. A tissue adhesiveaccording to any one of claims 1 to 11, characterized in that itcomprises factor XIII, preferably in an amount of at least 0.001 U/mg offibrinogen, particularly preferred at least 0.1 U/mg.
 13. A tissueadhesive according to any one of claims 1 to 12, characterized in thatit is free from kininogenic proteins.
 14. A tissue adhesive according toany one of claims 1 to 13, characterized in that it is present incombination with a solid surface as a fleece.
 15. A tissue adhesiveaccording to claim 14, characterized in that the solid surface is acollagen, gelatin or polysaccharide surface.
 16. A tissue adhesiveaccording to any one of claims 1 to 15, characterized in that in anenvironment of high fibrinolytic activity it is resistant to lysis for aperiod of time of at least 10 hours, preferably at least 15 hours.
 17. Atissue adhesive according to any one of claims 1 to 16, characterized inthat it is lyophilized.
 18. A tissue adhesive according to any one ofclaims 1 to 16, characterized in that it is present in solution.
 19. Atissue adhesive according to claim 18, characterized in that thesolution is deep-frozen.
 20. A tissue adhesive according to any one ofclaims 1 to 19, characterized in that it is present in virus-inactivatedform.
 21. A tissue adhesive according to any one of claims 1 to 20,characterized in that the elastase inhibitor is of recombinant origin.22. A tissue adhesive system, characterized in that it comprises atissue adhesive according to any one of claims 1 to 21 as one componentthereof.
 23. A tissue adhesive system according to claim 22,characterized in that it further comprises a component which comprisesthrombin and, optionally, calcium.
 24. A tissue adhesive system,characterized in that it comprises a fibrinogen component and acomponent which comprises an elastase inhibitor.
 25. A tissue adhesivesystem according to claim 24, characterized in that the component whichcomprises an elastase inhibitor comprises thrombin.
 26. A tissueadhesive system according to any one of claims 22 to 25, characterizedin that it further comprises an application device for the component(s)of the system, in particular a double-syringe system.
 27. The use of atissue adhesive according to any one of claims 1 to 19 for producing apreparation to be applied in fields with high fibrinolytic activity, inparticular in urology.
 28. The use of a tissue adhesive sytem accordingto any one of claims 22 to 26 for producing an application device to beemployed in fields with high fibrinolytic activity, in particular inurology.